The present invention relates to a device for feeding blanks to a bottom forming mandrel after opening each of the blanks from a flat form to a tubular form of square cross section.
Already known as such devices are those which comprise a magazine for accommodating flat blanks therein, transport means for withdrawing each of the blanks from the magazine and transporting the blank to a position on a phantom line extending outward from a mandrel, means for opening the flat blank to a tubular form of square cross section while the blank is being transported by the transport means, and a pair of guide rails for receiving the opened blank from the opening means and guiding the blank to the mandrel, the pair of guide rails having opposed recessed portions V-shaped in cross section for holding therebetween two corners of the blank on a diagonal thereof.
With the above device, the blank produces a great noise due to a repulsive force thereof upon the blank coming into striking contact with the guide rail when received by the guide rails. This noise is higher than any other noise released from packaging machines in noise level, whereas no measure has heretofore been taken to reduce the noise.